反应详情

Diisobutyl aluminum hydride (34.2 ml of a 1 M solution in toluene) was added to a solution of methyl 1-methyl-4-nitro-pyrazole-3-carboxylate (2.92 g) in anhydrous THF (100 ml) at −20° C. over a period of 5 minutes. The reaction was stirred at room temperature overnight and then poured into sat. citric acid (100 ml). The organic phase was separated and the aqueous washed with EtOAc (4×100 ml). The combined organic phases were washed with brine (100 ml), dried, filtered and concentrated in vacuo. The crude material was columned on silica (50 g), eluting with EtOAc. The product fractions were combined and washed with sat. aq. potassium sodium L-tartrate solution (3×100 ml) and brine (100 ml). The solvent was removed in vacuo to yield (1-methyl-4-nitropyrazol-3-yl)methanol as a pale yellow solid, 2.0 g, 74%.

1. customThe organic phase was separated
2. washthe aqueous washed with EtOAc (4×100 ml)
3. washThe combined organic phases were washed with brine (100 ml)
4. customdried
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. washeluting with EtOAc
8. washwashed with sat. aq. potassium sodium L-tartrate solution (3×100 ml) and brine (100 ml)
9. customThe solvent was removed in vacuo